Equalizing drive mechanism for airships.



H. N ATWOOD & D. D. STERNBERGH.

EQUALIZING DRIVE MECHANISM FOR AIRSHIPS.

APPLICATION FILED APR.29, 1915.

Patenwd July 27, 1915.

wvamtow tit DAVID JD. STERNJBERGH, 0F READING, PENNSYLVANIA.

EQUALHING DRIVE MECHANISM FOR'AIRSHIPS.

To all whom it'may concern:

Be it known that we, HARRY N. A'rwooo and DAVID D. STERNBERGH, citizens of the United States, residing at Reading, in the pelling devices and driving means therefor hereinafter fully described in connection with the accompanying" drawing and the novel features of which are pointed out in the claims. In these machines the action of each propeller upon the air exerts a drivingforward action upon the machine; this action being exerted in pushing forward the mass of the machine whenthe propeller is located rearwardly thereof, while if it is located forwardly it exerts a pulling action thereon. If propellers be located both forward and rearward of the machine, their pulling and pushing actions respectively will cooperate in driving the machine forward, with-a less-strain upon the supporting frame-work than if only forwardly located, or only rearwardly located, propellers are employed. Moreover if the actions of the forwardly located and rearwardly located propellers be equalized, the balance of the machine will be automatically maintained by their normal operation; the tilting tendency incident to the employment of either forwardly or rearwardly located propellers alone, being avoided even though the plane in which the propeller axes are most conveniently located be far above or below the median horizontal plane of the machine, and lateral equilibrium being maintained by the symmetrical arrangement of the propellers relative to the central vertical plane of the machine. In order that this automatic balance may be secured however, it is requisite that the effective actions of the several propellers be constantly equalized under actual conditions of service. The joint operation of both forwardly located and rearwardly located propellers, arranged in parallel planes of rotation, involves great changes of air conditions in each of said planes due to the action thereon of the propellers operating in the other plane, which changes vary with the speed of rotation of the propellers Specification of Letters Eatentl plied is merely illustrative.

Patented July 2?, 1915.

Application filed April 29, 1915. Serial No. 24,652.

and with the velocity of the machine itself and of the natural air currents. Theequalization of the effective actions of the symmetrically arranged propellers must therefore be promptly and automatically insured in order that the desired equilibrium of the machine may be maintained, and the mechanism employed must be simple in order to satisfactorily meet ordinary requirements.

Our invention consists essentially in providing in the simple -manner hereinafter de scribed, for the accomplishment of these re suits; and it at the same time permits of definitely varying the relative speeds of the propellers as required to efl'ect or facilitate the steering of the machine when desired.

Figure 1 is a diagrammatic lan view illustrating our invention as applied in simple manner to an airship of the hydro-aeroplane type; and Figs. 2 and 3 are similar front and side elevations of the same respectively.

The essential character of the several devices employed in our improved machine as indicated, being well known, and the invention consisting in the novel combination and arrangement thereof only, these devices are merely indicated diagrammatically without showing of their specific construction; and the type of machine to which they are ap- The motor 2 and seats 3 are mounted upon a supporting frame-work which comprises, as indicated, a il oatable body portion 4 to which upper and lower planes 5 and 6, with" standards 7, and rear rudder mechanism, are suitably secured.

lhe motor shaft 10 is shown operatively connected to a differential gearing indicated at 11; said gearing being adapted to equally divide the power, in well known manner, be tween transversely alined drive-shaft sections 12, 13, through which propeller shafts on opposite sides of the machine are respectively driven. Each of these drive-shaft sections is provided with a braking device, 14 and 15, which may be separately operated by .a conveniently located lever 16 so as to .unequally divide the power transmitted through the diflerential gearing 11 to the shaft sections 12, 13 when desired, as has been heretofore proposed in connection with propeller arrangements commonly employed.

In our improved apparatus, each propeller shaft carries a single propeller, but is shown, isfixed to a suitably mounted shaft relative to the central; vertical 1. plane. ,of: the

machine,v the combined 1' action ofthe. (propellers will automatically. maintain :the .machine,in equilibrium--..;-Each: of, the. forwardly located pair of propellers 20,: 20', as

21,,1which is connectedbyfa dififerential gearing 22'to adrive-shaft section 12. or .13, and alsotofan alined' propellerqshaft 23 carrying a-j'rearwardly located; propeller 24; so that theapower itransmitted.through said, driveshaft section lfi or. 13, )will be. equally divided between said front 1 and rear. propellers .20 and 24:, notwithstanding any inequality ofjair conditionsunder which they respectively operate, whether; such inequalities be due to the churningaction; oft the, ad-

" jacently arranged propellers themselves or otherwise, Thusif :one'propeller. were oper-' atingin a partial .vacuumas compared with another itwould be automatically speeded relatively .so as to equalize-the working ct and maintain the equilibrium: of the machine, Evenin case of-possible breakage this automatic actionywould: safeguard the machine and permit of. cutting oflr'. the

, motor if sdesiredh The. preferred form of drive shaftjllustrated, withits difi'erentially driven .and brake-controlled sections, permits the operator to guide the machine byrelatively speeding upt ie propellers on fone on other sideofthemachme, while at the same time maintaining-equalized T action ofthe front and rear propellers .on the re spective sides .thus enabling va satisfactory control ofthe machine which is otherwise impracticable.

The selected embodiment of our invention which .is -specifically. showns'and described may obviously be modified without departingfrom the invention as pointed out in the claims.

-What we claim is:

1. In an air-ship, the combination with a supporting frame and motor, of a pair of front-propeller shafts, a pair of rearropeller shaftseach of which is connecte to a front-propeller shaft by a differential gearing, and acommon drive shaft for all ofsaid propeller shafts. v :j In an air-ship, the combination with a supporting frame, a motor-shaft, and a propeller drive-shaft comprising separate sections and a connecting diflerential gearing, ofa pair of front-propeller shafts, and a pair of rear-propeller shafts each of which is connected to .a front-propeller shaft by a differential gearing operatively connected totone of said drive-shaft sections.

3. In an air-ship, the combination with a supporting frame, a motor-shaft, and a propeller drive-shaft comprising separate sections and a connecting differential gearing, of a pair of front-pro eller shafts, and a pair of rear-propeller s afts each of which is connected toa front-propeller shaft by a differential gearing operatively connected to one of said drive-shaft sections, each of saiddrive-shaft sections being provlded with separately operable braking means.

. 4. I n-an air-ship, the combination with a supporting frame and motor, of a plurality ofoforwardly located propellers and a plurality of rearwardly located propellers, arranged to operate in parallel vertical planes; each forwardly-located propeller bein connected to a rearwardly-located propel er by motor-driven differential gearing.

i .5. .In an air-ship, the combination with a supporting frame and motor, of a frontpropeller shaft and an alined rearpropeller shaft, said shafts being connected by motordrivcn differential gearing.

In testimony whereof we affix our signatures.

HARRY N. ATWOOD. DAVID D. STERNBERGH. 

